1. Field of the Invention
This invention relates to farming implements and, more particularly, to an apparatus for facilitating the continuous placement of seed in, and application of an additive to, soil. The invention also comprehends a method of soil treatment and seeding.
2. Background Art
In recent years there has been a trend away from the conventional method of planting and fertilizing fields. The conventional method is a multi-step process. First, the entire field is plowed by one or more passes of a cultivator unit. The prior year's residue is broken down and worked into the soil. The individual rows are eliminated so that the field has a generally homogeneous soil composition. Seed is planted and fertilizer applied in two additional, separate operations.
There are several drawbacks associated with conventional techniques. First of all, several passes over the field are normally required to adequately break up the soil and break down the residue and effect a mixing thereof. The cultivator unit must then be detached from a towing vehicle whereupon a planting unit can be substituted to be drawn by the towing vehicle. Interchange of implements can be difficult and time consuming. Further, the individual units are relatively expensive and must be separately stored when not in use and during the off season.
A further problem with this conventional technique is that the entire field is treated, whereas planting only occurs in a relatively small percentage of the area of a given field. As the entire field is plowed, there is substantial soil loss.
Recently, the federal government has decided to impose restrictions on the amount of ground cover that must be left in fields. Conventional techniques eliminate virtually all of the ground cover. It would be a prohibitive task to conventionally till the field and somehow replace the ground cover to comply with government regulations.
There have been many recent developments in no-till, min-till and ridge-till farming, which developments have been induced at least in part by ecological and economic considerations. These methods contemplate tilling of less than the entire field and maintaining ground cover in place on the field to thereby minimize erosion. These techniques allow soil preparation, seeding and fertilizing in a single pass over a field.
Normally, a plurality of planter units are drawn behind a vehicle in laterally spaced relationship. The planter units have at the leading end thereof a residue resituating structure, which may be a cooperating pair of toothed wheels. The wheels rotate to deposit residue on the sides of a row to be planted and at the same time pulverize and thereby aerate the soil in a planting row. Behind the residue resituating structure is a pair of Vee-opening wheels/disks which part the soil to define a seed slot. The seed is then deposited in the slot whereupon a pair of trailing closing wheels replace the soil in the slot.
With this latter structure, soil preparation and seeding can be accomplished with a single pass. In addition to planting the seed, it is also desirable to fertilize the soil in the vicinity of the seed. Typically, a starter fertilizer is deposited in the soil to quicken seed emergence and growth.
There are problems associated with known methods of applying fertilizer. For example, it is known to apply fertilizer at the leading portion of the planter unit. It is not uncommon for such planters to be devoid of any residue cleaning/resituating apparatus. The result is that much of the fertilizer is applied to the residue, rather than to the soil.
It is also known to apply the fertilizer directly into the seed slot. This direct application often results in an excessive amount of fertilizer being applied. If the seed is put in place before the application of the fertilizer, the fertilizer, which is applied under pressure, may undesirably resituate the seed. Also the seed may be damaged by direct contact with the fertilizer.
It is also known to spray the fertilizer at the trailing end of the planter unit. This often results in inadequate soil penetration by the fertilizer. High pressure spray application, to increase penetration, may resituate or altogether dislodge the seed.